Partially-chamberable laser boresight for small-bore firearms

ABSTRACT

The present invention provides a partially-chamberable laser bore sight primarily for small caliber rimfire handguns and rifles of 0.17 and 0.22 caliber. The partially-chamberable laser bore sight has a chamberable generally cylindrical laser housing, which contains the laser diode and lens. A battery housing that is perpendicular to and rigidly joined to the cylindrical laser housing contains the electro-chemical cells that power the laser diode. For a preferred embodiment of the invention, the cylindrical laser housing, which is preferably made of brass, is inserted into a mold and the battery housing is injection molded around the cylindrical laser housing. An ON/OFF switch is also mounted on the battery housing. The chamberable cylindrical laser housing is inserted within the breech, or chamber, of the firearm. The battery housing, with its ON/OFF switch, protrudes from the breech opening.

FIELD OF THE INVENTION

The present invention relates, generally, to aiming systems for firearms, and more particularly, to a chamberable laser boresight for small-bore rifles and handguns.

BACKGROUND OF THE INVENTION

Black powder—a mixture of potassium nitrate (saltpeter), charcoal and sulfur—was likely developed in China sometime between 700 and 900 A.D. Its discovery was followed by extensive experimentation and rapid innovation by Chinese scientists and inventors. This led to the manufacture of fireworks and rockets. Additionally, multiple grades of gunpowder were developed, as were a number of different types of weapons, including single-shot smooth-bore fire lances, multi-barreled guns, multiple-launch artillery rockets and the first cannon in the world made from cast bronze. During the next several centuries, gunpowder weapons spread from China, through the Middle East, and finally to Europe. Though apparently unknown in Europe as late as the mid-13th century, guns had become widespread throughout that continent by the end of the first quarter of the 14th century. Though tremendous innovation in firearm design and manufacture characterized the next century, they were hampered by the constraints imposed by crude machining technology and even more primitive metallurgy.

In the intervening centuries, firearms have become the predominant weapons used by mankind. Modern warfare since the late Renaissance has relied upon firearms, with wide-ranging effects on military history and history in general. This created a whole new kind of battle, which molded modern-era armies.

For handguns and long guns, the projectile is known as a bullet; in historical hand cannons, it was termed a shot. Though projectiles and shot were initially made from lead in a ballistic shape similar to that of a modern bullet, they were rapidly replaced with cast iron balls.

Until the mid-19th century, projectiles and propellant (black powder) were generally separate components used in a muzzle-loading firearm such as a rifle, pistol, or cannon. Sometimes for convenience a suitable amount of powder and a bullet were wrapped in a paper package, known as a cartridge. This evolved into the form of a tubular metal casing enclosing a primary igniter (primer) and the powder charge, with the projectile press-fit into the end of the casing opposite the primer. Cartridge ammunition was widely adopted, and as of World War I it had become the primary form of ammunition for small arms, tanks, and artillery. Mortars use a similar concept of encapsulation; however the projectile and casing are generally a one-piece unit that is launched from the firearm. Some short-range naval guns use cased ammunition, but many battleship and cruiser main guns use a shell and separate bagged powder measures, which are selected for a desired range.

As the sophistication and range of firearms increased, so did the need for accurate aiming of the projectile. The simplest sight is typically composed of front and rear aiming pieces that the gunner aligns with a target. Sights such as this can be found on many types of devices including weapons, surveying and measuring instruments, and navigational tools. On weapons, such sights are known as “iron sights,” and are usually cast or machined from a rugged metal such as iron or steel. Iron sights are not optical or computing sights. On many types of weapons they are built-in and may be fixed, adjustable, or marked for elevation, windage and/or target speed. There are two basic types of iron sights: notch (open) sights and aperture (closed) sights. Iron sights require considerable experience and skill, for the user must maintain proper eye position so as to simultaneously focus on the rear sight, the front sight, and the target at different distances—all while maintaining the three planes of focus in alignment.

Optical sights use optics that give the user an image of an aligned aiming point or pattern (also called a reticle) superimposed at the same focus as the target. Optical sights include both telescopic sights and reflective sights.

A telescopic sight is an optical telescope equipped with some form of graphic image pattern reticle mounted in an optically appropriate position in the optical system to give an accurate aiming point. Telescopic sights are used on a wide range of devices including guns, survey transits, and even as finderscopes on larger telescopes. Another type of optical sight is the reflector (or “reflex”) sight, a generally non-magnifying optical device that allows the user to look through a glass element and see a reflection of an illuminated aiming point or some other image superimposed on the field of view. These sights have been around for over 100 years and been used on all types of weapons and devices. Reflector sights were first used on weaponry in German aircraft towards the end of World War I. Over the years they became more sophisticated. The world War II Gyro gunsight was a reflector sight that added lead computing gyroscopes and electronics. During the 1950s and 60s, reflector sights incorporated radar range finding and other flight information. The head-up display represents the modern iteration of reflector sights.

Though the laser was invented in 1958, it was initially a bulky and expensive device. Nevertheless, the U.S. armed forces, which were seemingly unrestrained by cost factors, were quick to exploit the laser's military potential. One of the first uses of lasers by the military was as a laser target designator. A low-power laser pointer is used to indicate a target for a precision-guided munition launched from an aircraft or fired from a cannon. The guided munition adjusts its flight-path so as to home in on laser light reflected by the target, thereby enabling high-precision guidance of the munition to the designated target. Typically, the beam of the laser target designator is set to a pulse rate that matches that set on the guided munition to ensure munitions strike their designated targets and do not follow other laser beams which may be in use in the area. The target can be laser tagged by either aircraft or nearby ground forces. Lasers used for this purpose are typically infrared lasers, which cannot be visually detected by the enemy.

In 1984, Ed Reynolds of Laser Products Corp. was asked to build a laser sight to be mounted on an AMT Hardballer Long-Slide 0.45 ACP pistol as a movie prop. With the long sight attached to the even longer pistol, a body-builder-turned-actor named Arnold Alois Schwarzenegger used an external power supply in his coat pocket to activate the laser and make movie history. In fact, this pistol and sight combination became so iconic during the course of filming “The Terminator,” that it was included in the final movie poster. Laser sights have since come into widespread use on both rifles and handguns. A laser sight is a small, usually visible-light laser that has been mounted on a handgun or a rifle, with the laser aligned to emit a beam parallel to the barrel. Since a laser beam has low divergence, the laser light appears as a small spot even at long distances; the user places the spot on the desired target and the barrel of the gun is aligned (but not necessarily allowing for bullet drop, windage, distance between the direction of the beam & the axis of the barrel and the target mobility while the bullet travels). Laser sights are typically designed to mount on rails that are positioned either above or below the barrel of the firearm. Obviously, the more closely aligned with the path of the projectile, the more effective the laser as a sight. However, ofttimes the path of the ammunition round is not precisely aligned with the laser beam. Thus, even when a scope is aligned with the laser beam the scope is still misaligned with the projectile's path. To mitigate this problem, lasers have been designed to be mounted within the barrel of a rifle so as to more accurately align with the path of the projectile. Laser bore sights have been placed both at the extreme end of the barrel, as well as in the chamber directly behind the barrel. The breech installations appear to result in a slightly higher degree of alignment, as there is typically less wear in the chamber than in the rifle bore.

U.S. Pat. No. 6,622,414 to Oliver, et al. discloses a laser bore sight having a hollow, outer housing with an internally threaded, rear portion, and an externally-threaded end cap that is sized and shaped to engage the housing rear portion. The end cap includes a threaded, tubular stem having an annular rim, a dielectric spacer and a spring. The bore sight also includes a laser diode, a lens, a battery of three electrochemical cells, an electrically conductive spring, and an electrical conductor. The end cap is movable between an extended position with the spacer protruding from the end of the stem and a retracted position with the spacer recessed within the stem so as to allow the battery to make electrical contact with the end cap.

U.S. Pat. No. 7,905,043 to Hopkins discloses a boresight laser aiming system for firearms which provides a laser aiming beam through the mechanical action, chamber, and barrel of the operable firearm and through a specially configured live rimfire cartridge within the chamber, enabling a marksman to place the laser upon the target and fire the weapon simultaneously. The laser device may be installed concentrically with a light passage through the bolt, hammer, or other mechanism of the firearm, or may be offset with the light path guided by one or more reflective mirrors, prisms, etc. The firearm may comprise a rifle, semiautomatic pistol, revolver, etc. The live cartridge has concentric inner and outer tubes defining a toroidal explosive charge-containing chamber therebetween and a light passage through the innermost tube, and a bullet having a passage therethrough allowing light to pass through the live cartridge assembly when placed in the firearm chamber.

For the chamberable laser bore sights of the patents cited above, the battery of electro-chemical cells used to power the laser are housed in the chamberable casing. The problem with this design is that it is not easily adaptable to 0.17 and 0.22 caliber firearms—both of which use a chamber of 0.22 inch diameter—as the miniaturization required to enclose three electro-chemical cells, cell electrical contacts and a switch in a chamberable housing would make the laser bore sight excessively expensive and would result in a relatively short cell charge life.

SUMMARY OF THE INVENTION

The present invention provides a partially-chamberable laser bore sight primarily for small caliber rimfire handguns and rifles of 0.17 and 0.22 caliber. The partially-chamberable laser bore sight has a chamberable, generally cylindrical laser housing, which contains the laser diode and lens. A battery housing that is perpendicular to and rigidly joined to the cylindrical housing contains the electro-chemical cells that power the laser diode. For a preferred embodiment of the invention, the cylindrical laser housing, which is preferably made of a metal that is softer than the metal from which the gun chamber is made brass in order to minimize wear on the chamber when the cylindrical laser housing is inserted therein. Though brass is deemed to be an ideal metal for the cylindrical laser housing, other metals such as copper, aluminum or magnesium and alloys thereof can also be used. During manufacture of the laser bore sight, the metal cylindrical laser housing is inserted into a mold and the battery housing is injection molded around the cylindrical laser housing. An ON/OFF switch is also mounted within the battery housing. With the bolt of the handgun or rifle in the open position, the chamberable cylindrical laser housing is inserted with within the breech, or chamber, of the firearm. The battery housing, with its ON/OFF switch, protrudes from the breech opening.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a right-side elevational view of the new chamberable 22-caliber laser boresight;

FIG. 2 is a top plan view of the new chamberable 22-caliber laser boresight;

FIG. 3 is a rear elevational view of the new chamberable 22-caliber laser boresight;

FIG. 4 is a front elevational view of the new chamberable 22-caliber laser boresight;

FIG. 5 is a bottom plan view of the new chamberable 22-caliber laser boresight;

FIG. 6 is a plan view of the battery compartment cover;

FIG. 7 is a right-side elevational view of the battery compartment cover; and

FIG. 8 is an end view of the battery compartment cover.

FIG. 9 is a bottom plan view of the new chamberable 22-caliber laser boresight with the battery compartment cover removed;

FIG. 10 is a rear elevational view of the new chamberable 22-caliber laser boresight with the battery compartment cover removed;

FIG. 11 is a right-side elevational view of the new chamberable 22-caliber laser boresight, with the battery compartment cover removed;

FIG. 12 is a top plan view of the new chamberable 22-caliber laser boresight with the battery compartment cover removed;

PREFERRED EMBODIMENT OF THE INVENTION

The partially-chamberable laser bore sight for 0.22 caliber handguns and rifles which use heeled bullets will now be described in detail with reference to the attached drawing figures.

Referring now to FIG. 1, the partially-chamberable laser bore sight 100, that is intended for 0.22 caliber handguns and rifles, has a chamberable generally cylindrical laser housing 101, which contains the laser diode and a laser-focusing lens unit 102. A battery housing 103 that is perpendicular to and rigidly joined to the cylindrical laser housing contains the electro-chemical cells that power the laser diode. An ON/OFF switch 104 is also mounted on the removable cover 105 of the battery housing 103. With the bolt of the handgun or rifle in the open position, the chamberable cylindrical laser housing 101 is inserted with within the breech, or chamber, of the firearm. The battery housing 103, with its ON/OFF switch, protrudes from the breech opening. Referring now to FIG. 2, in this front view of the partially-chamberable laser bore sight 100, the laser diode 201, with its integral lens, is clearly visible within the cylindrical aperture 202 of the chamberable cylindrical laser housing 101. The release latch 203 of the battery cover 105 is also visible in this view.

Referring now to FIG. 3, in this top view of the partially-chamberable laser bore sight 100, the ON/OFF switch slider 104, the battery housing cover 105, and the release latch 203 are visible.

Referring now to FIG. 4, in this bottom view of the partially-chamberable laser bore sight 100, the ON/OFF switch slider 104 is visible. It can also be seen how the chamberable cylindrical laser housing 101 is molded within and protrudes from the battery housing 103.

Referring now to FIG. 5, in this rear view of the partially-chamberable laser bore sight 100, the removable cover 105 of the battery housing 103 is clearly visible.

Referring now to FIGS. 6, 7 and 8 the removable cover 105, which is shown in three views, has an L-shaped side profile (best seen in FIG. 7). The cover 105 has a battery cover panel portion 601 and a top panel portion 602. An offset tab 603 projects from a lowermost edge of the battery cover panel portion 601. The battery cover panel portion 601 also has a projecting latch 701, which is adjacent the top panel portion 602. The top panel portion has a knurled protuberance 702, which releases the removable cover 105 when pushed upwardly with a finger, and rectangular projection 703 adjacent the knurled protuberance 702.

Referring now to FIG. 9, the cover 105 has been removed from the partially-chamberable laser bore sight 100, thereby exposing the battery chamber 901 and the serrated release thereof and an upper a been removed from the battery housing 103, thereby exposing the battery compartment 901 and the ON/OFF switch assembly 902. Four 1.5-volt LR621 alkaline button cells 903 are shown installed in the battery compartment 901 between a positive electrical contact 904A and a negative electrical contact 904B. The projecting latch 701 on the top panel portion 602 fits into a recess 905 between the ON/OFF switch assembly 902 and a short partition 906 at the top of the battery housing 103.

Referring now to FIGS. 10, 11 and 12, the partially-chamberable laser bore sight 100 is shown with the cover 105 removed. In FIG. 12, a notch 1201 is visible which receives the rectangular projection 703.

When the battery compartment 901 is filled with charged cells and the ON/OFF switch slider 104 is moved to the ON position, a red laser beam is projected from the cylindrical aperture 202 of the chamberable cylindrical laser housing 101.

Although only a single embodiment of the new partially-chamberable laser bore sight 100 has been shown and described herein, it should be obvious to those having ordinary skill in the art that changes and modifications may be made thereto without departing from the scope and the spirit of the invention as hereinafter claimed. 

What is claimed is:
 1. A partially-chamberable laser bore sight for rimfire handguns and rifles comprising: a chamberable, generally cylindrical laser housing containing a laser diode and at least one laser-focusing lens; and a non-chamberable battery housing that is generally perpendicular to and rigidly joined to said generally cylindrical housing, said battery housing containing electro-chemical cells that power the laser diode; wherein said laser diode and said at least one laser-focusing lens produce a laser beam that is concentric with a barrel of the handgun or rifle in which said generally cylindrical laser housing is chambered.
 2. The partially-chamberable laser bore sight of claim 1, wherein said generally cylindrical laser housing is made of a structural metal.
 3. The partially-chamberable laser bore sight of claim 2, wherein said structural metal is brass.
 4. The partially-chamberable laser bore sight of claim 2, wherein said structural metal is selected from the group consisting of copper, aluminum, magnesium, zinc, tin and alloys thereof.
 5. The partially-chamberable laser bore sight of claim 2, wherein said battery housing is made of polymer resin and is fused to said laser housing.
 6. The partially-chamberable laser bore sight of claim 1, wherein said battery housing incorporates an ON-OFF switch.
 7. The partially-chamberable laser bore sight of claim 1, wherein said battery housing incorporates a removable cover that facilitates installation and replacement of electro-chemical cells within said battery housing.
 8. The partially chamberable laser bore sight of claim 1, wherein said chamberable, generally cylindrical laser housing is sized for handguns and rifles having a bore of at least 0.17 caliber and no greater than 0.22 caliber.
 9. A laser bore sight for handguns and rifles comprising: a chamberable, generally cylindrical laser housing containing a laser diode and at least one laser-focusing lens; a non-chamberable battery housing that is generally perpendicular to and rigidly joined to said generally cylindrical housing, said battery housing containing electro-chemical cells that power the laser diode.
 10. The partially-chamberable laser bore sight of claim 9, wherein said generally cylindrical laser housing is made of a structural metal.
 11. The partially-chamberable laser bore sight of claim 10, wherein said structural metal is brass.
 12. The partially-chamberable laser bore sight of claim 10, wherein said structural metal is selected from the group consisting of copper, aluminum, magnesium, zinc, tin and alloys thereof.
 13. The partially-chamberable laser bore sight of claim 10, wherein said battery housing is made of polymer resin and is fused to said laser housing.
 14. The partially-chamberable laser bore sight of claim 9, wherein said battery housing incorporates an ON-OFF switch.
 15. The partially-chamberable laser bore sight of claim 9, wherein said battery housing incorporates a removable cover that facilitates installation and replacement of electro-chemical cells within said battery housing.
 16. The partially chamberable laser bore sight of claim 9, wherein said chamberable, generally cylindrical laser housing is sized for handguns and rifles having a bore of at least 0.17 caliber and no greater than 0.22 caliber.
 17. A laser bore sight for handguns and rifles comprising: a chamberable, generally cylindrical, brass laser housing containing a laser diode and at least one laser-focusing lens; a non-chamberable battery housing that is generally perpendicular to and rigidly joined to said generally cylindrical housing, said battery housing containing electro-chemical cells that power the laser diode.
 18. The partially-chamberable laser bore sight of claim 17, wherein said battery housing is made of polymer resin and is fused to said laser housing.
 19. The partially-chamberable laser bore sight of claim 17, wherein said battery housing incorporates an ON-OFF switch.
 20. The partially-chamberable laser bore sight of claim 17, wherein said battery housing incorporates a removable cover that facilitates installation and replacement of electro-chemical cells within said battery housing. 